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List of Entomostraca found in Berwickshire. By Mr William Baied, 



Surgeon. 



The g^'eat Class Crustacea is divided by naturalists into two general 

 sections, the Malacostraca and Eatomostraca. The greater number of 

 the animals of this second division are contained within a regular shell, 

 and they have therefore received the name of Entomostraca, from the 

 two Greek words signifying " insects with a shell." Little attention 

 has been paid by British naturalists to the history of those exceedingly 

 interesting little animals, and what we do know of them, we owe 

 almost solely to our continental neighbours. Baker, indeed, in his 

 microscopical researches, has taken notice of several species, and 

 given plates of them, but he has done little to add to our information 

 with regard to their anatomy and economy generally. Joblot and 

 Ledermuller, in their works on microscopical objects, have given plates 

 also of several species ; whilst De Greer, Scheefier, and several other 

 celebrated continental naturalists of tlie last century, have added each 

 a little to our knowledge of them. Linneeus included all that he knew 

 in one genus Monoculus (so called from their possessing only one eye), 

 and gives descriptions of nine species only. Otho Fridericus Miiller is 

 the first regular historian of these animals who has done them justice. 

 To him it is that we owe the greater part perhaps of our knowledge 

 with regard to their economy ; to his labours we owe our acquaintance 

 with so many curious little creatures ; and to his eloquence is perhaps 

 owing the further researches and more detailed histories of succeeding 

 naturalists. His work on the Entomostraca, published in 1785, is one 

 of the most interesting memoirs in Natural History that we are 

 acquainted with ; and though it appears from later naturalists that he 

 has fallen into many errors, still it is the most complete and best history 

 of the Entomostraca that has ever been published. Since the time of 

 Miiller, much has been done to add to our knowledge of these inter- 

 esting animals ; and the memoirs of Jurine, father and son, Ramdohr, 

 and M. Straus, contain the most excellent and most minute histories of 

 detached genera that can be met with. Their researches have been 

 conducted with the greatest zeal and care, and their labours have been 

 abundantly crowned with success, their memoirs leaving little to be 

 done by succeeding naturalists but to add to the species. Hermann 

 (fils), Daudebart de Ferussac, Adolphe Brongniart, and other continen- 

 tal naturalists, have also given some excellent memoirs upon detached 

 genera and species, whilst our own celebrated Leach is the only British 

 naturalist we know that has paid any attention to the history of the 

 Entomostraca ; his labours, too, being chiefly directed to the parasitic 

 animals of the division. It surely is not from want of interest belong- 

 ing to them, that the naturalists of this country have neglected the 

 Entomostraca, for many of them are worthy of all admiration. " The 

 multifarious and complicated structure of their body," says Miiller in 



